An approach is provided in which a system selects a first processor as a master Time of Day (TOD) processor in a first TOD topology in response to determining that the first processor is directed connected to an oscillator. The system then assigns a second processor as an alternate master TOD processor to a second TOD topology based upon determining that the second processor is on a different node than the first processor. The system configures to the first TOD topology and, when the system detects a TOD failure, the system re-configures to the second TOD topology.